Phenyl alkenyl ethers

ABSTRACT

PHENYL ALKENYL ETHERS WHEREIN THE ALKENYL GROUP CONTAINS A CARBON CHAIN OF 8 OR 9 CARBON ATOMS AND THE TERMINAL UNSATURATED DOUBLE BOND CAN BE EPOXIDIZED OR EPISULFIDIZED, WHICH ARE USEFUL IN UPSETTING THE HORMONE BALANCE OF PESTS SUCH AS INSECTS.

U ited States Patent OfliCe 3,769,320 Patented Oct. 30, 1973 3,769,320 PHENYL ALKENYL ETHERS Maclhukar Subraya Chodnekar, Basel, Albert Pfiffner and Norbert Rigassi, Arlesheim, Ulrich Schwieter, Reinach, Basel-Land, and Milos Suchy, Basel, Switzerland, assignors to Holfmann-La Roche Inc., Nutley, NJ.

No Drawing. Filed Apr. 20, 1970, Ser. No. 30,297 Claims priority, application Switzerland, Apr. 30, 1969, 6,597/69 Int. Cl. C07c 69/78 U.S. Cl. 260-473 R 12 Claims ABSTRACT OF THE DISCLOSURE Phenyl alkenyl ethers wherein the alkenyl group contains a carbon chain of 8 or 9 carbon atoms and the terminal unsaturated double bond can be epoxidized or episulfidized, which are useful in upsetting the hormone balance of pests such as insects.

SUMMARY OF THE INVENTION In accordance with this invention, it has been found that compounds of the formula:

wherein R is methyl or ethyl; R is hydrogen, methyl or ethyl; R is hydrogen or lower alkyl; K and L are individually hydrogen; A taken together with B form a carbon to carbon bond, an oxygen bridge, or a sulfur bridge; K and L taken together form a carbon to carbon bond; X is O; Y is hydrogen, halogen, lower alkyl, or lower alkoxy; and Z is carboxyl or lower alkoxycarbonyl, and the dotted bonds can be optionally hydrogenated;

upset the hormone balance of pests such as insects to protect them from growing and reproducing.

The compounds of Formula I are prepared by reacting a halide of the formula:

wherein A, B, K, L, R R and R are as above; and Hal is a halogen;

with a compound of the formula:

Z (III) wherein M is a metal in Group I of the periodic table; X and Y are as above; and Z is formyl, carboxyl, lower alkoxycarbonyl, aryloxycarbonyl or aralkoxycarbonyl.

DETAILED DESCRIPTION OF THE INVENTION fined as above. Among the preferred lower alkoxycarbonyl groups are included methoxycarbonyl, ethoxycarbonyl and isopropoxycarbonyl.

The compounds of Formula I are useful in the control of pests such as Tineola biselliella (clothes moth), Ephestia kulmiella (meal moth), Dysdercus cingulatus (cotton bug), Blatella germanicq (cockroach).

In contrast to most of the known pest-control agents which kill, disable or repell the pests by acting as contact poisons and feed poisons, the compounds of Formula I above prevent maturation and proliferation of these pests by interfering with their hormonal system. In insects, for example, the formation into the imago, the laying of viable eggs and the development of laid normal eggs is disturbed. Furthermore, the sequence of generations is interrupted and the insects are indirectly killed.

The compounds of Formula I above are practically non-toxic to vertebrates. The toxicity of these compounds is greater than 1000 rug/kg. body weight. Moreover, these compounds are readily degraded and the risk of accumulation is thereforeexcluded. Therefore, these compounds can be used without fear of danger in the control of pests in animals, plants, foods and textiles.

Generally, in controlling invertebrate animals, the compounds of Formula I above thereof are applied to the material to be protected, e.g., foodstuffs, feeds, textiles, plants in concentrations of from about 10" to 10-" gm./ cm. of the material to'be protected. Generally, it is preferred to utilize the compounds of Formula I above in a composition with a suitable inert carrier. Any conventional inert carrier can be utilized.

The compound of Formula I can, for example, be used in the form of emulsions, suspensions, dusting agents, solutions or aerosols. In special cases, the materials to be protected (e.g., foodstuffs, seeds, textiles and the like) can also be directly impregnated with the appropriate compound or with a solution thereof. Moreover, the compounds can also be used in a form which only releases them by the action of external influences (e.g., contact with moisture) or in the animal body itself.

The compound of Formula I above can be used as solutions suitable for spraying on the material to be protected which can be prepared by dissolving or dispersing these compounds in a solvent such as mineral oil fractions; cold tar oils; oils of vegetable or animal origins; hydrocarbons such as naphthalenes; ketones such as methyl ethyl ketone; or chlorinated hydrocarbons such as tetra.- chloroethylene, tetrachlorobenzene, and the like. The compounds of Formula I above can also be prepared in forms suitable for dilution with water to form aqueous liquids such as, for example, emulsion concentrates, pastes or powders. The compounds of Formula I above can be combined with solid carriers for making dusting or strewing powders as, for example, talc, kaolin, bentonite, cal-, cium carbonate, calcium phosphate, etc. The compositions containing the compound of Formula I above can contain, if desired, emulsifiers, dispersing agents, wetting agents, or other active substances such as fungicides, bacteriacides, nematocides, fertilizers and the like. These materials which are to be protected act as bait for the insect. In this manner, the insect, by contacting the material impregnated with the compound of Formula I above, also contacts the compound of Formula I above.

It will be appreciated from the foregoing that the invention also includes within its scope an agent useful for the control of pests which contains as an essential active ingredient or essential active ingredients one or more of the phenyl derivatives of Formula I in association with a compatible carrier material. In addition, the invention includes within its scope a method of rendering a locus subject to or subjected to attack by pests immune to or free wherein K and L are as above; A and B are a carbon to carbon bond or an oxygen bridge; R is phenyl lower alkyl, lower alkyl or hydrogen;

and compounds of the formula:

KB L @AAQIAo-Q CH; C-ORm wherein A, B, K, L and R are as above.

Among the preferred compounds of Formula I are included compounds of the formula:

wherein R A and B are as above.

When R is lower alkyl in the compounds of Formulae I-a, I-ai, I-b and I-bi, the preferred lower alkyl group is methyl. In accordance with the preferred embodiment of this invention, the group A0R10 is substituted in the para position.

Among the preferred compounds of this invention are included:

p- (3,6,7-trimethyl-octa-2, 6-dienyl) oxy] -benzoic acid methyl ester;

p-[ 6,7-epoxy-3 ,6,7-trimethyl-oct-2-enyl -oxy] -benzoic acid methyl ester;

p 3,6,7-trimethyl-octa-2,6-dienyl) oxy] -benzoic acid ethyl ester;

p-[ 3,6,7-trimethyl-octa-2,6-dienyl) -oxy] benzoic acid.

Among the preferred halide starting materials are included compounds of the formula:

L Wm wherein K and L are as above; and Hal is halogen; and

CH: (II-b) wherein K and L areas above; and Hal is a halogen.

Among the compounds of Formula II-a are included the following: 7

I (II-a1) wherein Hal is a halogen.

Among the compounds of Formula II-b are included the following:

wherein Hal is a halogen.

The halide starting materials of Formula II and the starting materials of Formula III are known substances and they can be reacted with each other to produce a compound of the Formula I above in accordance with methods known per se.

For example, a halide of Formula II preferably a chloride or bromide, is expediently dissolved in an inert organic solvent and the solution allowed to act on a compound of Formula III (formed in statu nascendi). The compound of Formula III (an alkali metal salt) can advantageously be formed by reacting the corresponding phenol, or alcohol with an alkali metal hydride, alkali metal alcoholate or alkali metal hydroxide, preferably-sodium hydride, a sodium alcoholate or sodium hydroxide in a known manner. The salt formation and the reaction of the salt with the halide are expediently carried out in the presence of a suitable inert organic solvent. When sodium hydride is used, suitable solvents are, for example, dioxan, tetrahydrofuran, dimethylformamide or diethyl ether, when sodium methylate is used a suitable solvent is for example, methanol or when sodium hydroxide is used suitable solvents are for example, methanol, ethanol or acetone. The reaction of the halide with a phenol or alcohol can also be carried out in the presence of a carbonate, preferably potassium carbonate.

The reaction of a halide of Formula II with a compound of Formula III is expediently carried out at a temperature between 0 C. and the boiling temperature of the reaction mixture, advantageously in the presence of h'examethyl phosphoric acid triamide. The reaction mixture can be worked up in a conventional manner. For example, it can be poured onto ice and extracted with diethyl ether, the ether extract washed with water, dried and evaporated. The resulting derivative of Formula I can be purified by adsorption; for example, on kieselgel or aluminum oxide.

When Z in the compound of Formula I above is an acid group, the acid can be converted into an acid chloride by conventional means such as by treatment with thionyl chloride, preferably in the presence of pyridine. The acid chloride can be transformed into an ester by reaction wit-h an alcohol utilizing conventional procedures well known in the art.

If desired, the derivatives of Formula I in which A and B taken together form a carbon to carbon bond can be epoxidized or episulfidized in accordance with methods known per se.

The epoxidation of derivatives of Formula I can expediently be carried out by dissolving the derivative concerned in an inert solvent (especially in a halogenated hydrocarbon such as methylene chloride or chloroform) and treating the solution obtained with an organic peracid (e.g., with perbenzoic acid, rn-chloroperbenzoic acid or perphthalic acid) at a temperature between 0 C. and room temperature. Alternatively, the derivative concerned can be suspended in water and treated with an appropriate amount of an inert solvent (e.g., with dioxan, tetrahydrofuran or 1,2-dimethoxyethane) such that a homogenous concentrated solution is obtained. N-bromosuccinimide is then introduced portionwise into this solution at a temperature between 0 C. and room temperature. The resulting bromohydrin can be smoothly converted into the desired epoxide by the action of alkali, especially by the action of sodium methylate in methanol.

The introduction of a sulfur bridge into derivatives of Formula I can be effected in various ways. If, for example, thiourea is allowed to act on a halohydrin (preferably on the bromohydrin) of a derivative of Formula I there is firstly formed an isothiouronium salt. This salt is also formed when thiourea is allowed to act on an epoxide of Formula I, at temperatures of from 0 to 30 C. in the presence of a mineral acid. The isothiouronium salts obtained can be readily converted into the desired epithio derivatives of Formula I by treatment with a base.

Insofar as the side chain is unsaturated, the derivatives of Formula I are obtained according to the process as a cis/trans isomer mixture. The mixture can, for example, be separated into the individual isomeric forms by adsorption on a material having selective activity. For example, the isomer mixture can be dissolved in an inert organic solvent (e.g., in hexane, ether or acetic acid ethyl ether) and adsorbed on kieselgel. The isomers adsorbed in diiferent zones can be eluted with one of the solvents named hereinbefore or a mixture thereof and isolated. In individual cases, the isomer mixture can also be separated by fractional distillation or by fractional crystallization.

An aldehyde of Formula I obtained by reacting a halide of Formula II with a compound of Formula III in which Z' signifies formyl, can be oxidized to the corr e sponding acid in a known manner. The oxidation can advantageously be carried out at room temperature with the aid of silver oxide formed in an aqueous medium from silver nitrate and sodium hydroxide. After the oxidation, the aqueous solution is extracted with diethyl ether and the ether extract is discarded. By acidification of the aqueous phase the sodium salt present therein is converted into the free acid which can be extracted (e.g., with ether or methylene chloride) and isolated from the extract in a conventional manner.

The following examples are illustrative but not limitative of this invention.

EXAMPLE 1 In an inert gas atmosphere, 8 g. of a 50% by weight suspension of sodium hydride in mineral oil are washed with two 25 ml. portions of tetrahydrofuran, then introduced into 100 ml. of tetrahydrofuran and treated dropwise with a solution of 25 g. of p-hydroxy-benzoic acid ethyl ester in 100 ml. of tetrahydrofuran. 40 g. of l-bromo-3,6,7-trimethyl-octa-2,6-diene in 100 ml. of hexamethylphosphoric triamide are subsequently added dropwise and the resulting mixture is heated under reflux conditions for two hours, cooled, poured onto ice and exhaustively extracted with diethyl ether. The ether extract is washed with water, dried over sodium sulfate and evaporated under reduced pressure. The residual oily p-[( 3,6, 7-trimethyl-octa-2,-6-dienyl)-oxy]-benzoic acid ethyl ester can be purified by adsorption on kieselgel; boiling point: 150-152 C./0.1 mm. Hg; n =1.5241.

EXAMPLE 2 In a manner of Example 1, p-hydroxy-benzoic acid is reacted with l-bromo 3,6,7 trimethyl-octa-2,6-diene to produce p-[(3,6,7-trimethyl-octa-2,6-dienyl)-oxy]-benzoic acid (melting point=128-129 C.); p-hydroxy-benzoic acid methyl ester is reacted with 1-chloro-3,6,7-trimethyl-octa-2,6-diene to produce p-[(3,6,7-trimethyl-octa-2,6- dienyl)-oxyl]-benzoic acid methyl ester (boiling point: 205 -206 C./1 mm. Hg; n 24=1.5231); and p-hydroxybenzoic acid benzyl ester is reacted with 1-bromo-3,6,7-

6 trimethyl-octa-2,6-diene to produce p-[(3,6,7-trimethylocta-2,6-dienyl-oxy]-benzoic acid benzyl ester (n 1.5520).

EXAMPLE 3 A solution of 2 g. of p-[(3,6,7 trimethyl octa 2,6- dienyl)-oxy] -benzoic acid methyl ester in 150 ml. of methylene chloride is treated dropwise at 0 C. with a solution of 1.35 g. of by weight m-chloro-perbenzoic acid in 100 ml. of methylene chloride. After 15 minutes, the resulting mixture is successively washed with 2% by weight aqueous sodium bisulfite solution, 5% by weight aqueous sodium bicarbonate solution and water, dried over sodium sulfate and evaporated under reduced pressure. The residual p-[(6,7-epoxy-3,6,7-trimethyl-oct-2 enyl)-oxy]-benzoic acid methyl ester can be purified by adsorption on kieselgel; n =l.5112.

EXAMPLES 4 AND 5 In Examples 4 and 5 hereinafter, which relate to tests demonstrating the activity of the phenyl derivatives provided by the invention, the phenyl derivatives are referred to by way of the letters indicated in the following list:

(A) p-[(3,6,7-trimethyl-octa 2,6 dienyl)-oxy]-benzoic acid methyl ester (B) p-[(6,7-epoxy-3,6,7-trimethyl oct-2-enyl)-oxy]-benzoic acid methyl ester.

EXAMPLE 4 A cotton disc (10 cm?) is sprayed with a solution of active substance in acetone. After drying, 30-60 freshly laid eggs of the meal moth (Ephestia kuhniella) are placed on the disc. The same is done with an untreated cotton disc and a cotton disc sprayed only with acetone. The discs are placed in a cage and kept at 25 C. and relative humidity. The development of the eggs is registered over a period of a few days and the results are A filter-paper strip (90 cm?) is sprayed with a solution of active substance in acetone. After drying, 3-4 pairs of freshly moulted images of the cotton bug (Dysdercus cingulatus) are placed on the strip. The same is done with an untreated filter-paper strip and a filter-paper strip treated only with acetone. The development of the eggs laid daily is noted and the results are evaluated egg mortality: no development of the embyros in the eggs laid on filter-paper strips soaked with active substance).

Results:

Amount of active substance Number Number Mortality Active substance (gJemJ) of eggs of larvae (percent) A 10- 325 0 100 10- 420 280 33 Control with acetone 270 262 3 Control without acetone 410 7 What is claimed is: 1. compound of the formula:

CH: R: K Z wherein R is methyl or ethyl; R is hydrogen, methyl or ethyl; R is hydrogen or lower alkyl; K and L are individually hydrogen; A taken together with B form a carbon to carbon bond; K and L taken together form a carbon to carbon bond; Y is hydrogen, halogen, lower alkyl, or lower alkoxy; and Z is carboxyl or lower alkoxycarbonyl.

2. The compound in accordance with claim 1 wherein said compound is:

B L /L,\

wherein K and L are as above; A and B are a carbon to carbon bond; R is lower alkyl or hydrogen.

3. The compound in accordance with claim 2 wherein said compound is:

on, 0R

wherein R A and B are as above.

4. The compound in accordance with claim 3 wherein R is lower alkyl.

5. The compound in accordance with claim 4 wherein said compound is p-[(3,6,7-trimethyl-octa-2,6-dieny1)- oxy]-benzoic acid methyl ester.

6. The compound in accordance with claim 4 wherein said compound is p-[(3,6,7-trimethyl-octa-2,6-dienyl)- oxy]-beinzoic acid ethyl ester.

7. The compound in accordance with claim 3 wherein R is hydrogen.

wherein K and L are as above; A and B are a carbon to carbon double bond and R is lower alkyl or hydrogen.

10. The compound of claim 1 wherein said compound has the formula:

wherein A and B' are a carbon to carbon double bond; and R is lower alkyl, or hydrogen.

11. The compound of claim 10 wherein R is lower alkyl.

12. The compound of claim 11 wherein said compound is p- (3-ethyl-6,7-dimethyl-nona-2,6-dienyl) -oxy] -benzoic acid methyl ester.

References Cited Lauer et al.: J. Am. Chem. Soc., 67, 1254 (1945). Upjohn Co., Chem. Abst. 56, 8646g (1962). Bennett et al.: Chem. Abst., 33, 4220 LORRAINE A. WEINBERGER, Primary Examiner J. F. TERAPANE, Assistant Examiner U.S. Cl. X.R.

260-240, 468 K, 514 K, 521 R, 521 A; 424275, 278, 305, 308, 317 

